Seven South Korean sailors were missing after their cargo ship collided with a larger freighter and sank off the coast of Japan, South Korea's Coast Guard said.

Seven South Korean sailors were missing after their cargo ship collided with a larger freighter and sank off the coast of Japan, South Korea's Coast Guard said on Tuesday.

According to the coast guard, a 4,255-tonne South Korean-registered ship, Orchid Pia, sank after colliding with a Panamanian-registered automobile carrier at around 2:15 am some 12 km east of Japan's Izu Oshima island.

Nine Indonesian crew along with the seven South Korean sailors were on board the ship.

The 10,833-tonne Panamanian ship was also sinking but all the 11 sailors on board were rescued by Japanese coast guard officials, South Korea's Yonhap News Agency said.

The Orchid Paia was carrying some 5,050 tonnes of steel coil from Japan to the southern South Korean port of Yeosu when the accident took place, the news agency added.